1 in 25 men raising children not their own

HealthCentral: "Calling it a Pandora's Box with broad health implications, British researchers say genetic testing is informing about 4 percent of fathers that a child they are raising is not their own."
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The report appears in the August issue of the Journal of Epidemiology and Community Health.

The authors said they based their findings on international published scientific research and conference abstracts released between 1950 and 2004.

The study found that rates of "paternal discrepancy" range on average from less than 1 percent to as high as 30 percent, depending on the group of people looked at.

...in the United States, rates more than doubled to 310,490 between 1991 and 2001, they noted.

In Great Britain, about one-third of pregnancies are unplanned, and about one in five women in long-term relationships has had an extramarital affair, the researchers reported